The Scarlets will be under no illusions that they have to do 'the double' over the Saints when the two sides come face-to-face at Parc y Scarlets on Saturday.
The Welsh side, who have reached three Heineken Cup semifinals, know they need to get their campaign back on track after their 19-13 defeat to Munster in Irelandin their last game.
The Scarlets are five points behind Pool leaders, Munster, and need a victory to keep in touch with the Irish province and to keep their dream of a first quarter finals place in four years alive.
The Saints, who won the Heineken Cup in 2000 and were beaten finalists in last season's tournament, have endured a miserable European campaign and have already failed to qualify for the knockout stages.
The English Premiership outfit, though, could still have a major bearing on whether the Scarlets and Munsterqualify for the quarter-finals because they play both of them in the final two games of the Pool.
Scarlets: 15 Liam Williams, 14 George North, 13 Scott Williams, 12 Jonathan Davies, 11 Viliame Iongi, 10 Rhys Priestland, 9 Gareth Davies, 8 Ben Morgan, 7 Rob McCusker, 6 Aaron Shingler, 5 Dominic Day, 4 Lou Reed, 3 Deacon Manu, 2 Matthew Rees, 1 Iestyn Thomas.
Replacements: 16 Ken Owens, 17 Phil John, 18 Rhodri Jones, 19 Josh Turnbull, 20 Jon Edwards, 21 Rhodri Williams, 22 Stephen Jones, 23 Gareth Maule,
Northampton: 15 Ben Foden, 14 Chris Ashton, 13 George Pisi, 12 Tom May, 11 Vas Artemyev, 10 Steve Myler, 9 Martin Roberts, 8 Roger Wilson, 7 Phil Dowson, 6 Calum Clark, 5 Mark Sorenson, 4 Samu Manoa, 3 Brian Mujati, 2 Dylan Hartley, 1 Soane Tonga'uiha.
Replacements: 16 Mikey Haywood, 17 Alex Waller, 18 Paul Doran-Jones, 19 Christian Day, 20 Ben Nutley, 21 Lee Dickson, 22 Ryan Lamb, 23 Scott Armstrong
Date: Saturday, January 14
Venue: Parc y Scarlets
Referee: Alain Rolland (Ireland)
Assistant referees: Leo Colgan (Ireland), Michael Black (Ireland)
TMO: Sean Flannery (Ireland)
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